Tampons and other types of absorptive media are routinely inserted into body cavities, such as a woman's vagina, to absorb menstrual fluid, blood and other kinds of body fluid. One convenient way to position such absorbent tampons into a body cavity is through the use of an applicator. Comfortable and clean insertion of the absorbent tampon is key to repeated sale of such applicators. In addition, the applicator should be capable of inserting the absorbent tampon into the body cavity using an acceptable amount of expulsion force.
Tampon applicators are available in a variety of shapes and sizes with the two-piece telescopically assembled design being the most prevalent. In the two-piece applicator, the tampon is housed in a hollow outer tube and is expelled into a woman's vagina by an inner member that is telescopically mounted in the outer tube and acts as a plunger. Some tampon applicators utilize a hollow tube having an open insertion end through which the tampon is always exposed while other applicators utilize a completely closed or partially closed design. A thin film membrane can cover the insertion end of an applicator to completely enclose the forward end of a tampon while folds can be used to partially enclose the forward end of a tampon and protect it from contamination. Still other applicators, especially plastic applicators, have a plurality of flexible petals formed on the forward end of the outer tube which can flex radially outward to allow the tampon to be expelled. It will be appreciated that the diameter of the applicator, the material from which it is formed, the basic configuration of the applicator, the size and shape of the tampon positioned in the applicator, as well as the ease of opening the forward end of the applicator will all influence the force required to expel the tampon therefrom. The expulsion force should be kept reasonably low to permit proper functioning of the applicator.
While many have tried to design and manufacture tampon applicators having these improved qualities, there still remains a need for a tampon applicator that is more comfortable to use. Those applicators having an open forward end tend to expose the dry absorbent fibers of the tampon to the interior walls of a woman's vagina and this can cause irritation during insertion. Commercially available plastic and cardboard applicators, using a plurality of petal tips separated by slots, can sometimes pinch or cut the vaginal tissue of a woman during insertion and cause discomfort.
U.S. Pat. No. 5,782,793 issued to Nielsen et al. discloses a tampon applicator having a semi-spherically shaped pleated tip. The pleats of Nielsen are formed by doubling the material upon itself and then pressing the material into place. As can be seen in FIG. 8 of Nielsen, the pleats 50 have a thickness dimension “t” defined by three layers of material 34. The doubling of material upon itself to form the pleats leads to high expulsion forces which can cause the applicator to deform or cause the tampon to be inserted incorrectly.
Applicators for delivering materials into a body cavity typically comprise a tubular insertion member having an insertion end and a gripper end opposite thereof, and an elongate expulsion member slidably fitted within the tubular insertion member for expelling the contained materials. The gripper end will generally incorporate features to allow a user to more or less securely hold the applicator during use, which includes the following steps: inserting the applicator into a body cavity, expelling a substantially enclosed material contained by the applicator, and withdrawing the applicator from the body.
Over the years, attempts have been made to improve the gripping features. One approach is to significantly reduce the diameter of the applicator in the gripper end. While a reduced diameter grip may help in preventing fingers from slipping during insertion, there is little or no resistance offered in the opposite direction during the expulsion step. This is a step with which many users have difficulty.
Another approach to improve the grip of the applicator during use is to incorporate projections, such as in the form of a ring, at the base of the applicator member being inserted into the body. Similar to the disadvantage of applicators employing a reduced diameter in the gripping end, projections typically provide only a single direction of resistance. In most cases, the resistance provided is intended to aid during the expulsion step.
While many have tried to design and manufacture tampon applicators having these improved qualities, there still remains a need for a tampon applicator that has gripping features that provide limited resistance to finger slip during use.
Common corrugation techniques such as those used in the production of corrugated paperboard or cart onboard package containers involve performing a process operation on a paper or fiber sheet or web that is generally planar in form when introduced into the corrugating process. Additionally, the sheet or web often contain two opposed side edges; and in the case of a sheet it often also possesses two opposed end edges.
For purposes of this invention, a tube blank is the structure subjected to a corrugating process and since a tube blank often does not possess opposed side edges (i.e. the surface of the tube blank is connected about the perimeter in a closed generally hollow form), and/or a tube blank is generally not planar when presented to the corrugating process. Therefore, non-planar corrugating techniques are required.
Accordingly, there is a need for a new and improved method of forming and corrugating an insertion tip on the end of the tampon applicator and corrugating and forming a grip for facilitating comfortable insertion of an absorbent tampon into a woman's vagina while having a low expulsion force.